使用弹簧测力计，如果指针指在零刻度线下方就开始测量，所测拉力的大小与真实值相比（　　）x

卡车和联合收割机以同样快慢、向同一方向前进，下列有关它们的说法中，正确的是(       )

若氧元素只有¹⁶O、¹⁸O两种核素，下列说法正确的是（　　）

请根据句意从方框中选择合适的单词，并用其适当形式填空，使句子通顺。

 (1)Look! They are watching the film Lost in Thailand with ____  on the Internet.

(2)My father's ____  birthday happens to be on Father's Day.
(3)The Internet is____  used in most families in our country today.
(4)Those beautiful paintings don’t belong to us. They are those____ .
(5)It will make you feel ____  if you sit too long in front of the computer.

如图所示，甲图是 ____机的示意图，乙图是 ____机的示意图．