英語のことわざ

One swallow doth not a summer make

In England, the arrival of swallows, which are a type of bird, signal the beginning of summer. People used to wait for them, watching for them, because they signaled the beginning of the warm weather. But just because you have seen one swallow, it does not necessarily mean that it is the beginning of summer. You have to have seen more than one. You have to have seen many of them. If you have just seen one, it could mean that the one swallow had arrived early by mistake. Therefore, according to this proverb, just because one good thing happens, it does not mean everything will go well. Or just because you have successfully completed one part of a project, it does not mean that the whole project is ompleted." "Doth" is the old form of "does."