David，is that man your Chinese teacher?—It___________ be him．He’s having a meeting．

He often does some washing _____ Sunday. [ ]

I ________ a letter from him this morning. I felt very excited.

What happened in Indonesia?—________ December, 2004, a strong earthquake hit Indonesia and the big tsunamis (海啸) followed. [ ]

Can you tell me _____ the birdwatchers in Zhalong Nature Reserve? I only know that _____ of them are from our school.