Before a problem can be solved，it must be obvious____the problem itself is.

g had such ________ to its masterthat it would not leave him, even when he was dead

“I haven’t heard from Henry for a long time.”—— “What do you suppose_____ to him?”

下列各句中，没有语病的一句是（ ）

The number of students in our school ____about 30,000 and ______them study hard.