One should not only observe but also help.
不但要看，而且要帮。
Things here are not only inexpensive but also of good quality.
这儿的东西又便宜又好。
Not only Jim but also his wife saw her.
不但吉姆而且他妻子也见到了她。
Not only cancer, but also heart and lung disease are influenced by smoking.
不仅是癌症，还有心脏病和肺部疾病也都会受吸烟影响。
Laboratory work needs not only accurate measurements but also correct calculation.
实验工作不但需要准确的.测量，而且需要准确的计算。