把下例句子连成含有动词不定式的句子

Be careful to do exercises. The teacher told her students.

________________________________________________

Laboratory work is your chance to learn science first-hand. It can be fun but you must be careful to prevent injury. Listen closely when your teacher reads and explains the rules before your first lab lesson.

1.Your teacher will probably tell you the rules above        the first lab lesson.

   A. before            B. since            C. during           D. after

2.Before every experiment, you should       .

   A. taste the chemicals first

B. clean all the apparatus

   C. read all instructions carefully

D. report all the accidents to the teacher

3.When you are not sure how to use all apparatus,       .

   A. try them on your own                  B. put them back

   C. ask your teacher for help                 D. read the rules carefully

4.It is clear that you can       .

   A. bring food into the lab

B. enter the lab anytime

   C. smell chemicals as you like

D. learn science directly in the lab

5.If you get chemicals on the clothing, you can find ways to solve it in the part       .

A. Before the Experiment                 B. First Aid

C. During the Experiment                 D. After the Experiment

Laboratory work is your chance to learn science firsthand. It can be fun but you must be careful to prevent injury. Listen closely when your teacher reads and explains the rules before your first lab lesson.

LABORATORYRULES

Throughout the lesson ●Do not enter the science lab without the teacher’s permission. ●No food or drinks are to be allowed in the science lab.

Before the Experiment ●Read all instructions carefully before every experiment. ●Prepare all apparatus（仪器） and arrange them so that you will not knock them over while doing the experiment.

During the Experiment ●If you are unsure of how to use any apparatus or how to operate, ask your teacher for help. ●Never smell or taste chemicals unless your teacher gives permission.

After the Experiment ●Wash all apparatus after use and return them to the places where they were. ●Throw waste materials in proper waste baskets.

First Aid ●Report all accidents to your teacher immediately. ●If you spill（溅出）any chemicals onto your body or clothing ,wash with plenty of water and report to your teacher.

(   )51.Your teacher will probably tell you the rules above______ the first lab lesson.

A. before  B. since    C. during    D. after

(   )52. Before every experiment , you should ___.

A. taste the chemicals first    B. clean all the apparatus

C. read all instructions carefully  D. report all the accidents to the teacher

(   )53. When you are not sure how to use all apparatus,____.

A. try them on your own     B. read the rules carefully

C. ask your teacher for help   D. put them back

(   )54. It is clear that you can ____.

A. bring food into the lab    B. clean the lab anytime

C. smell chemicals as you like    D. learn science directly in the lab

(   )55. If you get chemicals on the clothing ,you can find ways to solve it in the part____.

A. Before the Experiment     B. First Aid

C. During the Experiment     D. After the Experiment

Laboratory work is your chance to learn science firsthand. It can be fun but you must be careful to prevent injury. Listen closely when your teacher reads and explains the rules before your first lab lesson.

LABORATORY  RULES
Throughout the   lesson	·Do not   enter the science lab without the teacher’s permission. No food or drinks are   to be allowed in the science lab.
Before the   Experiment	·Read all   instructions carefully before every experiment. · Prepare   all apparatus（仪器）and arrange them so that you will   not knock them over while doing   the experiment.
During the   Experiment	·If you are   unsure of how to use any apparatus or how to operate, ask your teacher for help.   ·Never smell   or taste chemicals unless your teacher gives permission.
After the   Experiment	·Wash all   apparatus after use and return them to the places where they were. ·Throw waste   materials in proper waste baskets.
First Aid	·Report all   accidents to your teacher immediately. ·If you   spill（溅出）any chemicals onto your body or clothing,   wash with plenty of water   and report to your teacher.

1. 1.

   Your teacher will probably tell you the rules above ______ the first lab lesson

   1. A.
      before
   2. B.
      since
   3. C.
      during
   4. D.
      after
2. 2.

   Before every experiment, you should______.

   1. A.
      taste the chemicals first
   2. B.
      clean all the apparatus
   3. C.
      read all instructions carefully
   4. D.
      report all the accidents to the teacher
3. 3.

   When you are not sure how to use all apparatus,______.

   1. A.
      try them on your own
   2. B.
      read the rules carefully
   3. C.
      ask your teacher for help
   4. D.
      put them back
4. 4.

   It is clear that you can ______.

   1. A.
      bring food into the lab
   2. B.
      enter the lab at any time
   3. C.
      smell chemicals as you like
   4. D.
      learn science directly in the lab
5. 5.

   If you get chemicals on the clothing, you can find ways to solve it in the part ______.

   1. A.
      Before the Experiment
   2. B.
      First Aid
   3. C.
      During the Experiment
   4. D.
      After the Experiment