before, discover , fast, in, come, watch , so, fast it, ago , shine, not can

Light travels at a speed(速度) which is about a million times 1 . ________ than that of sound.  2. ________ one second, light travels about 300,000 kilometers, but sound travels only 340 meters. You can get some idea of this difference by  3. ________  the start of a running match. If you stand far away from the starter(发令员), you can see smoke 4.________ from his gun 5.________ the sound reaches your ears.

The fast speed of light produces some strange facts. The nearest star is 6. ________ far away that light which you can see from it tonight started to travel to you  four years  7. ________ at a speed of nearly two million kilometers every minute. The light from some of tonight’s started on 8. ________ journey towards you even before you were born.

So, if we want to be honest(诚实), we 9.  ________ say , “ The stars are shining brightly tonight.”  We have to say, “ The stars look nice. They were 10. ________ four years ago but their light has just reached our earth. ”

用ago, before, from, since, for填空

1．We stay at the seaside (海边) ________ a week every August.

2．He has played the piano ________ three years.

3．My mother will be away ________ Tuesday on Saturday.

4．Linda has never heard of him ________.

5．I met her two days ________.

6．Remember to turn off the lights ________ you leave here.

7．We've known each other ________ 1995.

8．Say goodbye ________ you go.

9．They had the meeting ________ 2：00 to 4：30.

10．He joined the army ________ five years ago.

用ago, before, from, since, for填空

1．We stay at the seaside (海边) ________ a week every August.

2．He has played the piano ________ three years.

3．My mother will be away ________ Tuesday on Saturday.

4．Linda has never heard of him ________.

5．I met her two days ________.

6．Remember to turn off the lights ________ you leave here.

7．We've known each other ________ 1995.

8．Say goodbye ________ you go.

9．They had the meeting ________ 2：00 to 4：30.

10．He joined the army ________ five years ago.

Before long they moved to a new neighborhood.

[　　]

A. Not too long ago

B. Long before

C. Once upon a time

D. Not long after that

Before long they moved to a new neighborhood.

[　　]

A. Not too long ago

B. Long before

C. Once upon a time

D. Not long after that