Whale beachings（搁浅）_______ be caused by factors such as illness, or disorientation（迷失方向）caused by extra noise in the oceans, ______ shipping or oil and gas drilling.

—   willyoufinishdoingthework?—In a fewweeks.

-- Look at that girl. Is it Susan?--No, it _______ be her. She has gone back to her home town .

—Hey! Any idea about learning abroad?—You ________ google the College Board to learn the names of colleges you ________ be interested in.

—Must I finish the work today?—No, you    .