Tom is tall, but his sisters, Mary and Kathy, short.
Smile to the world, ________ the world will smile back to you.
-- ________ can you finish this English examination? -- In about one and a half hours.
-- Would you like some milk? --________.
You __ drive your car so fast. It's very dangerous.
--What is Miss Gao's favourite________? --She is always in pink. Don't you know?