beingood在...表现良好,在...有效果但begoodin极少作文固定短语
Ithasbeenprovedtobegoodinpracticeresult.实践效果良好.
Tohavefinepoliticalandprofessionalqualityandtobegoodinconduct.
有良好的政治、业务素质和良好的品行;
begoodat擅长于...at后面跟名词或动名词(即动词+ing)
Alexisverygoodatlanguages.擅长语言
She'sgoodatmakingthings.