Do all colours work as な adjectives or い adjectives when using て form 'and'? In a sentence such as "my phone is white and small", would it be 私のけいたいは白いで小さいです。OR ～けいたいはしろくて～? Also, if the colour were to change to a less basic colour, like はいいろ, would the 'and' form change?
- 白くて is correct but 白いで is ungrammatical, because 白い is an i-adjective. 白で is acceptable, but 白くて is much more common. Similarly, you should usually say 赤くて小さい, 青くて小さい, 黒くて小さい, and so on, while 赤で/青で/黒で is also sometimes used.
- 灰色で is correct but 灰色くて is ungrammatical, because 灰色 is a no-adjective. Similarly, you should say 緑色で小さい, オレンジで小さい, ピンクで小さい, and so on.