1、当“only+状语”位于句首时，其后习惯上要用部分倒装。其中，only后的状语可以是副词、介词短语、从句等。（1）Only in this way can we learn English. 只有这样才能学会英语。（2）Only then did I understand what she meant. 只有到那时我才明白她的意思。（3）Only by shouting was he able to make himself heard. 他只有叫喊才能让别人听到他。注意，在only后作状语的是从句时，从句不要用倒装，要部分倒装的是主句。
2、在句首的only如果后面跟了副词、介词短语或从句等状语，则主句用倒装结构。如only后跟的是主语，就不用倒装结构了。例如：（1）Only when the war was over in 1918 was he able to get back to work.（2）Only in this way can you learn English well.（3）Only after a bitter struggle was the aim achieved.
3、注意，only和所修饰的状语如果不在句首，则不倒装。如：The boy was helped out only when his father arrived in a hurry.Only then did he realize the importance of English只有在那时候他才意识到英语的重要性。