Only by making constant efforts and never stopping making progress can we ...

这不是only 引出的倒装句吗？Only 引出状语（包括时间、地点、方式等状语，包括副词、介词短语、从句等）后，句子产生部分倒装：

Only then did I realize the importance of English. 只有在那时，我才认识到英语的重要性。

Only recently have I heard of her.直到最近我才听说她的情况。

Only in this way can we learn maths well. 只有这样，我们才能把数学学好。

Only in the reading-room can you find him. 你只有在阅览室才能找到他。

Only by working hard can you succeed. 只有努力工作你才能成功。

Only by shouting was he able to make himself heard.  他只有叫喊才能让别人听到他。

Only after she died was I able to appreciate her. 只有到她死后我才认识到她的价值。

Only when one loses freedom does one know its value. 一个人只有在失去自由后才知道自由的可贵。

Only when the war was over in 1918, was he able to get happily back to work. 直到1918年战争结束后，他才能愉快地重新投身于研究工作。