In 27:39-40 these pronouns are singular and refer to Esau, but what Isaac says also applies to Esau's descendants (See: [[rc://en/ta/man/translate/figs-synecdoche]]).
"Dew" is drops of water that form on the plants during the night. This can be made explicit in the translation. AT: "the night mist from the sky to water your crops" (See: [[rc://en/ta/man/translate/figs-explicit]])
Here "sword" stands for violence. AT: "You will rob and kill people in order to get what you need to live" (See: [[rc://en/ta/man/translate/figs-metonymy]])
This speaks about someone having a master as if the master's control over the person were a yoke that the person had to carry. AT: "you will free yourself from his control" (See: [[rc://en/ta/man/translate/figs-metaphor]])