选A、B均可。你的问题，属于英语算式中的主谓一致，不过，你给的句子漏掉了times（倍数）。应为：Six times seven ______ forty-two. （意为：6倍的7是42.）

大致规则是：

    两数相加、相乘，谓语动词可用单数形式，也可用复数形式；两数相减、相除，谓语动词用单数形式。

    1. Fifteen and five is/are/makes/equals/equal/is equal to/are equal to twenty.

15加5等于20。

    2. Five times six is/are/makes/make/equals/equal/is equal to/are equal to thirty.

5乘以6等于30。

    3. 15 minus 5 leaves/makes/equals/is equal to 10.

15减去5等于10。

    4. Fifteen divided by 5 makes/equals/is equal to 3.

15除以5等于3。

同意刘老师解答！

Six sevens are forty-two.是正确的

英语加减乘除运算的表示方法

(1)加法：加法运算通常用and, plus, add 等表示。

Seven and (plus) eight is (are, make(s)) fifteen. 

7加8等于15。

If you add ten to eight, you get eighteen. 

10加8等于18。

(2)减法：减法运算通常用 minus, from, take (away) (from) 等表示。

Eight minus five is [leaves] three. 

8减 5等于3。

4 from 20 leaves 16. 

20减4余16。

Ten take away four is [leaves] six. 

10减去4得6。

If you take five from twelve, you’re left with seven. 

12减去5得7。

If you take four away from ten, that leaves six. 

10减去4得6。

(3)乘法：乘法运算通常用 times, multiplied by, twice 等表示。

Five times three is [equals] fifteen. 

5乘以3等于15。

Five eights are forty.

5乘以8等于40.

Five multiplied by two equals ten. 

5乘以2等于10。

What is twice two? 2乘2是多少?

(4)除法：除法运算通常用 divided by, into 

等表示。

Twelve divided by four is [makes] three. 

12除以4等于3。

Four into twelve is [makes] three. 

12除以4等于3。

Six seven ______ forty-two.

A. are    B. is

选哪个？

【答】

Six seven ______ forty-two.

A. are    B. is

是错误的。应该是：（1）

Six times seven ______ forty-two.

A. are    B. is（两个都正确）

或者（2）

Six multiplied by seven ______ forty-two.

A. are    B. is(正确答案)

【注意】如果times后面的数是one，或者用multiplied by表示“乘”，谓语动词用单数； 如果times后面的数不是one，谓语动词单数或复数都可以。例如：五乘三等于十五。Five times three is fifteen. or 5 multiplied by 3 is 15. or Five times three are fifteen.（摘自《外研社汉英词典》第三版）

Four times one is four.(4x1=4) (摘自《刘毅英语语法宝典》p.397)

8 (multiplied) by 5 equals 4o. (8x5=40) (摘自《刘毅英语语法宝典》p.397)