【題目】Work hard, ________ you can't get a better grade in the test.

【題目】-Happy birthday, Kate. Here's a gift ________ you.

【題目】Don't forget to take your passport with you ________you leave for the airport.

【題目】________ helpful advice you gave us on protecting ourselves yesterday.

【題目】Once you make a decision, you'd better ________ your mind from time to time.

【題目】Don't touch that wire with a wet hand. We ______ always be careful with electricity.

【題目】Parents should always keep an eye on little children, ______ they may get lost.

【題目】That photo in my childhood shows one of ______ memories of mine.

【題目】These kinds of mushrooms look ______ but you should never eat them.

【題目】Although the Internet makes ______ life more convenient, it sometimes causes trouble.