__________ these tips, and your time _______ doing research on the Internet _________ much worthwhile.

Humans can’t live _______ air.—I agree with you.[ ]

Thedisabled (残疾) peoplefeelgrateful_______you_______yourhelp.[ ]

The first thing _____ I should do is to work out a study plan for the next term.

Thank you for _____________me with my English.