[译] 他不善于搞科研。
[误] He is bad for making scientific researches.

[正] He is bad at making scientific researches.
[注] be bad at（= not skilful）意为"不善于"，又如：She is bad at speech. 她不善于讲话。be bad for（= harmful to）作"对……有害"解，如Smoking is bad for health. 吸烟有害于健康。/Very small print is bad for the eyes. 字体太小对眼睛有害。