When do I need to use an apostrophe?什么时候用撇号？Answer these questions, using the words in parentheses. Put the apostrophe in the right place.用句后括号中的词或词组来回答问题, 注意撇号的位置.'It's' (with an apostrophe) should be use...
Their absoluteness mainly refers to infiniteness and invariability while relativity denotes finiteness and variability.其绝对性主要是指它们的无限性和不变性,其相对性主要是指它们的有限性和可变性....