455. – I must apologize for ______you so much.

　 --- That’s all right.

A. to have troubled　　　　 B. bringing trouble to

C. being troubled　　　　　 D. having troubled

454. Man _______a battle against pollution at once.

A. must start fighting　　　 B. had to start to fight

C. is starting fighting　　　 D. is beginning fighting

453. Our teacher told us ________ story _____ we all never forget it.

A. so an interesting; so that　　　　　 B. so interesting a; which

C. such interesting a; that　　　　　 D. such an interesting; that

452. _______, the workers still continued working.

A. Since it was snowing　　　　　 B. It was snowing

C. Late as it was　　　　　　　　 D. Though it was early

451. The English teacher often said in class, “Let’s ______in English.”

A. talk　　 B. say　　 C. spoke　　 D. tell

450. Among them I like this kind of food ______, for it is ____ sugar and water.

A. best; mostly　　　　　　　　 B. best; most

C. most; best　　　　　　　　　 D. most; mostly

449. – Excuse me, have you ever been to Japan ?

　 --- __________.

A. No, I don’t　　 B. Never　　 C. Sorry, I can’t　 D. Don’t mention it

448. Was it _____ Tom’s carelessness ____ your keys were all lost?

A. because; which　　　　　　 B. for; what

C. because of; that　　　　　　 D. since; /

447. After a long walk, they were _______ very tired, but _____ of them would stop to rest.

A. all; neither　 B. both; none　 C. all; none　 D. both; neither

446. – There is a football match tomorrow, you know.

　 --- What ____pity! I haven’t got ______ticket for tomorrow.

A. a; a　 B. a; the　 C. the; the　 D. the; a