just like 可以连接一个完整的句子吗,为什么,这是什么用法.

1、just只是用来修饰like表示“就像..”的意思,连词依然是“like”.
2、这里用with是因为,be popular with...是固定搭配,能补充点，这种常见的固定搭配吗这个很多，你可以直接在百度上搜索“固定搭配”。以下是部分常见的“形容词固定搭配”：be present at 出席 be pound of 以......自豪，因......感到满意 be ready for 为......准备好be rich in 富于be satisfied of 相信be satisfied with 对......满意，满足于be second to 次于be short for 是......的缩写（简称）be short of 短缺be sick for 渴望be sick in bed 病在床上be sick of 对......感到厌倦be sorry for 对......感到抱歉be strict with 对......要求严格be subjected to 遭受be suited to适合于be supposed to (do) 应该，非......不可be sure of 坚信，确信be sure to (do) 一定，必定be surprised at 对......感到惊奇be through with 结束be tired from 因......而疲乏be tired of 厌烦，对......厌倦be tired out 疲倦，急了be true of 适用于be unconscious of 不知道......be unequal to 无法胜任......的be unfit for 不适合，不胜任be useful to 对......有用be well up in 精通，熟悉be wild with joy 欣喜be willing to (do) 乐意......be worried about 为......担心be worth (doing) 值得（做）be wrong with 有点毛病，有些不舒服