55. All the students envied him _____having succeeded in the TOFEL test.

Can I come here on Saturday or Sunday—Sorry, you can come _____on Saturday _____ Sunday. We only work on weekdays.

We’d better hold more such activities, ______ students can combine study with fun.

Hurry up，kids！The school bus ________for us！ (2013·四川，3)

Teachers have to constantly update their knowledge inorder to maintain their professional _____