Here evils and troubles are described as if they were human and could find people. AT: "When this people experiences many evils and troubles" (See: [[rc://en/ta/man/translate/figs-personification]])
This can be stated in active form. AT: "their descendants will not forget to keep it in their mouths" (See: [[rc://en/ta/man/translate/figs-activepassive]])
# it will not be forgotten from the mouths of their descendants
This can be stated positively. AT: "their descendants will remember to keep it in their mouths" (See: [[rc://en/ta/man/translate/figs-activepassive]])
# it will not be forgotten from the mouths of their descendants
The idiom "forget it from the mouth" means to stop speaking about it. AT: "their descendants will not stop speaking about it to each other" (See: [[rc://en/ta/man/translate/figs-activepassive]])
# the plans that they are forming
What people plan to do is spoken of as if it were a physical object. AT: "what they plan to do" (See: [[rc://en/ta/man/translate/figs-metaphor]])
You may need to supply the words omitted by the ellipsis. AT: "the land that I promised I would give to them" (See: [[rc://en/ta/man/translate/figs-ellipsis]])