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to 4. It’s important _____ the piano well. of him to play B. for him to play C. of him playing D. for him playing 5. It is not _____ you to learn three languages at the same time. for B. difficult to C. easy for D. easy of isn’t ____ to go to school. A . old enough B. enough old C. big enough D. enough big 7. He wasn’t __ with his knife. A . careful enough B. enough careful C. carefully enough D. enough carefully 8 The young man is not ___ the box. A. enough strong to carry B. strong enough carrying C. strong enough to carry D. enough strong carrying 9. The water isn’t warm enough for the children____. A. to swim B. to swimming C. to swim in D. to swimming in