服盐类泻药引起腹泻的原因是（）
A.肠黏膜分泌增多
B.肠腔内渗透压增高
C.肠黏膜吸收障碍
D.肠蠕动过快
E.肠腔内渗透压低
参考答案：B
根据下列句子的意思及所给出的汉语提示，写出空缺处的单词，固定短语或固定搭配的正确形式。
1. Please write an ________ (邀请) letter to________ (邀请) your pen friend.
2. Don't ________ (担心, 担忧) about your Chinese. We can help you.
3. It is ________ (必要的) for us to keep everything clean and tidy.
4. —Is China ________ from the USA? —Yes. There are many ________ between China and the USA. (不同).
5. We have a lot of friends ________ ________ ________(全世界)
根据fIDIC《施工合同条件》的规定，当工程量的变更与某项工作规定的具体费率的乘积超过了接受的合同款额的（）时，可以对该项工作规定的费率或价格加以调整。
A.0.01%
B.1%
C.0.1%
D.10%
