如有需要可选修额外的课程。Additional courses may be taken if desired.这门课程包括十个必修单元和五个选修单元。The course consists of ten core modules and five optional modules.某些课程是必修的,其他是选修的。Certain courses are compulsory, others are optional....
Mr Leach is on holiday and was not available for comment.利奇先生休假了,不方便作出评论。Nitrates leach from the soil into rivers.硝酸盐由土壤渗入江河。Liquid water can leach soluble materials from the interface.液态水能够从界面溶解出可溶性物质....