下面每句都有一个标点符号错误，该用标点处未用标点或标点符号用错，改正错误或补写标点。 1.I don't know how to answer that question? 2.Don't forget to cross your ts. 3.Ouch I think I've broken my toe. 4.It was James' father not her mother,who visited her recently. 5.It is a dependable fool proof method. 6.Our company produces many fine products it has,in fact,a reputation for quality merchandise. 7.In the first quarter prices rose 5 per cent;in the second quarter,3 per cent and in the third 7 per-cent. 8.Frank Stanley,III will replace his grandfather,Frank Stanley,Sr.,as president of the company. 9.Stallions yield the highest prices;but mares can also be extremely expensive. 10.Help,Help!Someone has fallen into the river.