press the red button ,_______you will setoff the alarm.

If you have trouble pronouncing these words, you can repeat them over and over again ________ you are comfortable with them．

Many memories of old times were _______ by the conversation we had that evening.

At least 100 people lost their lives in the fire, _____ 7 children.

My sister is three years ______than I. She is _______young_____go to school.