根据提示用适当的介词完成句子。 1.—Where are my books? —They're o________ the sofa. 2.—Where is your pen? —It's i________ the pencil case. 3.—Where are my shoes? —They're u________ the bed. 4.—Where is my cat? —It's b________ the door.
【单选题】The Advantages and Disadvantages of Buying Lottery Tomato Ripening Tomatoes give off minute quantities of ethylene gas which is active in starting the natural ripening process. If left to nature, howe...