1.这个的确叫做部分倒装.
所谓部分倒装,是指把句子的be动词/助动词/情态动词提前,其他成分保持不变.
如：Only in this way can you solve this problem.
= You can solve this problem only in this way.
而所谓的全部倒装,是指把句子的主语和谓语位置对调,其他成分保持不变.
如：Here comes the bus!
= The bus comes here.
2.此句之所以容易被误认为是全部倒装,是因为此句的be动词is刚好同时也是句子的谓语.
如果主句谓语不是be动词,就很容易看出该句型是部分倒装了.
再如：So fast did he run that nobody could catch up with him.