I am sorry to hear that you are worried about the variety of English you have been learning.

    Firstly, the differences between British and American English may surprise those____have learned English for years.There____(be) almost no differences in grammar and only a few differences in vocabulary.British and American people have no difficulty____(understand) each other.They watch films and televisions from each other's countries for____(please).

    Secondly, there isn't only one British____American English.For example,all major cities in the UK have____ (they) own dialects with different accents from each other.Sometimes these accents can be____(hard) to understand for even a British person than some Americans.Also,there are Englishes from many other countries.People who speak these Englishes usually also manage____(communicate) with other English speakers without any problems.

    All learners need to be able to understand English spoken and written by as many people as possible and they need to be able to speak English so that as many people as possible can understand them.You should concentrate on this goal,not on____to speak “British” or “American” English.

    I hope this is____(help).

在水平桌面上有一个盛有水的容器，木块用细线系住没入水中（水未溢出），如图甲所示．将细线剪断，木块最终漂浮在水面上，且五分之二的体积露出水面，如图乙所示．

下列说法正确的是（  ）