Leaves are found _______ all kinds of trees, but they differ greatly ________ size and shape.
------Do all _______ you think are right, _______ others say. ------yes, I________.
As you ______ new words in context, it is a very good method for you to guess their meanings.
Charles Babbage is generally considered ____ the first computer.
Look at the trouble I am in. If only I _____ your advice.
This is ____________you are mistaken.