Water, which seems to be so simple and common, is ______ makes life possible.
When you are reading fast, your eyes will be one or two word groups ahead ___your mind is taking on.
Who was that _____called him “comrade?”
---- Do you want tea or coffee?----____ . I really don’t mind.
I would appreciate____ very much if you could change the plan a bit to make it more workable.
He is one of the students, who, I’m sure, always do _____best.