回答网友这个问题之前，我们先了解一下as well as的二种不同用法。

1 as well as...是副词well 的同级比较结构。即主句主语做某事和从句主语做某事做得一样好。例如：

She sings as well as her sister does. 她的歌唱得和她姐姐一样好。

She sings as well as she plays the piano. 她的歌唱得和她弹钢琴一样好。

= Her singing is as good as her playing the piano.

2 as well as 作为准并列连词，连接相等的语法结构。A as well as B = not only B, but also A.

由于as well as为准并列连词，并不是真正意义上的并列连词表示等立关系，而是表示强调 A 信息的不对等并列，所以，已知信息要作为B项，新信息作为A 项。这也是 as well as连接二个主语时，谓语的动词的数要与A 的人称和数保持一致的原因。例如：

 Men, as well as women, have a fundamental right to work.  （误）

本句为错误。男人有工作的权利是已知信息，妇女有工作的权利才是需要强调的。二个主语的位置错乱。下句才是正确的。

Women, as well as men, have a fundamental right to work. （正）

Tom, as well as his friends, often help the old man do house work. (误）

Tom, as well as his friends, often helps the old man do house work. （正）

as well as连接的二个主语，谓语动词要与A主语保持一致。

现在我们讨论网友的问题。

由于as well as 为well 的同级比较结构时，as是个连词，后接比较分句，即含有限定动词作谓语，虽然as 分句经常采用省略结构，所以当as well ，as做not only...but also之意的准并列连词用时，就不用来连接二个从句，以避免与well的同级比较结构相混淆。如果逻辑表达要求连接二个分句时，就采用not only...but also结构，而不用as well as结构。二个分句的主语相同，谓语动词不同时，则可以as well as，但B分句的谓语改为动名词结构。例如：

She not only orders the equipment but (she) also negotiates the licences.

注意上句中的but she also 也可以省略she, 这样not only...but also连接的就是二个谓语。因为but是真正意义上的并列连词。如果用as well as, 则后面的分句谓语要改为动名词：

She negotiates the licences as well as ordering the equipment.

= She not only orders the equipment but (she) also negotiates the licences.

如果在as well as后用限定分句，语法没有错，但就不是”不但...而且..."的意思了，而是“和...做得一样好的意思。

She negotiates the licences as well as she orders the equipment.

这句话的语法没有错。但意思是：她订购设备的工作做得很好，她谈判许可证的工作做得同样好。而不再是：她不但订购设备，她还谈判许可证事宜。柯林斯是在讲解as well as作为准并列连词表示"不但...而且..."的时的用法，所以说as well as后面不能接限定分句，并没有说这个句子本身语法有错误。

结论：

1 当 A as well as B 作为准并列连词，表示”不但...而且...“的意思时，B项通常不能为限定分句（即不能用限定动词形式），以避免与副词as的同级比较结构相混淆。

2 这种用法的as well as可以并列二个不定式，但B项的不定式必须省略to. 例如：

I have to feed the animals as well as look after the children. 我不但要照看孩子，还得喂动物。

3 副词well的同级比较结构不受此限制，as比较分句的限定动词根据比较分句的一般要求，可以保留，也可以省略。注意以下二句的结构和意义的不同：

She sings as well as she plays the piano. 她的歌唱得和她弹钢琴一样好。

She sings as well as playing the piano. 她不但弹钢琴，她也唱歌。