Could you please refrain__________smoking in the lecture hall?

A. Phong walks fast, and it’s really hard for keep up with him

B. Phong walks fast, so it was really hard to keep up with him

C. Phong walks fast, and it’s really hard to keep up with him

D. Phong walks fast, so it was really hard for keep up with him

B. to show that there were no weapons in hands.

C. Abandoned children should be brought up in orphanages so as to they can be safe.

D. Abandoned children should be brought up in orphanages so as that they can be safe.

D. cautiously

A. These baskets were made in thin bamboo strips.

B. These baskets were made by thin bamboo strips.

C. These baskets are made of thin bamboo strips.

D. These baskets are made with thin bamboo strips.

A. He wondered when to leave for France.                 

B. He wondered when I should leave for France.

D He wondered whenhe leave for France.