～ても・でもEven if, Even though

てもいい is a common grammatical pattern used to give or ask for permission. At the core of this expression is the ても conditional pattern. Though てもいい is often translated as 'Can I…' or 'May I…' in English, the literal meaning is 'Is it okay even if I...?' In this sense, the basic ても pattern has an even wider range of uses. For example, 負けてもあきらめない means '(I) won't give up even if (I) lose.'

ても is a highly versatile structure meaning 'even if,' used widely in both speech and writing. In contrast, ようが～まいが is much more formal and mainly found in written or academic contexts. Both forms can express 'whether or not'. For example, 食べても食べなくても and 食べようが食べまいが both mean 'whether or not (you) eat', but the latter is more emphatic and formal.

Both forms can express the meaning of 'even if'. ても is more versatile and commonly used in both everyday speech and writing, while にせよ・にしろ is more limited in usage, with にせよ sounding especially formal. Note that ても is often used in the pattern てもいい 'it's okay to (A)' to ask or give permission, whereas にせよ・にしろ is not used this way.

ても and たって both mean 'even if' or 'even though,' with the main difference being tone and formality. ても is widely used in both everyday speech and writing, while たって is more casual and emphatic, typically found in informal conversation. Aside from tone, their meaning is nearly identical, e.g., 行っても and 行ったって both mean 'Even if I/you/etc. go...'

Both forms can express the meaning of 'even if' or 'even though.' ても is more versatile and commonly appears in expressions like てもいい 'it's okay to (A)' to ask or give permission. としても has a stronger hypothetical nuance similar to 'Even assuming that…', and can also serve as a more emphatic version of として. For example, 私としても大変だ ('It's tough even for me.').

さえ and ても can both express the meaning of 'even' and sometimes overlap, especially with nouns. For example, 子どもでもできる and 子どもさえできる both mean 'Even a child can do it.'. However, they diverge when ても expresses permission, such as in 行ってもいい ('You can go.') or when さえ means 'if only', e.g. お金さえあれば 'as long as you have money'. In these cases, the two expressions are not interchangeable.

たとえ～ても is a stronger and more limited version of ても used in hypothetical situations. For example, たとえどこに行っても 'no matter where you might go' is a more emphatic version of どこに行っても 'wherever you go'. However, in cases where ても expresses permission, e.g. てもいい 'you can (A)', たとえ would not be used, since the meaning is not strongly hypothetical.

もし and ても both express hypothetical situations, but in different ways. もし appears before a clause to emphasize the condition, similar to 'if' or 'supposing that', while ても is attached to the verb itself. Because they fill different roles, they can be used together, e.g., もし雨が降っても 'even if it rains'. もし can also pair with other conditionals like たら or ば.

ても has the core meaning of 'even if.' One common use is in Verb + てもいい to ask or give permission. For example, 食べてもいいですか？ means 'Can/May I eat this?' (literally, 'Is it okay even if I eat this?') More broadly, ても can also express contrast. For example, 寒くても行きます means 'I'll go even if it's cold.'

The particle でも can attach to question words to mean 'any~' as in 誰でも 'anyone' or なんでも 'anything', or follow nouns to suggest a casual option, like in お茶でも飲みませんか？ ('Want some tea or something?'). This looks similar to ても, which becomes でも after nouns and な-adjectives, but means 'even if', as in 日本語でも大丈夫です ('It's fine even if it's in Japanese.').

ても is an extremely versatile expression used to mean 'even if' in a wide variety of contexts, both in everyday speech and writing. In contrast, ようが～まいが is a highly formal expression that specifically means 'whether or not' and occurs primarily in written or academic language. For example 食べようが食べまいが and 食べても食べなくても both mean 'whether or not (you) eat', but the former is far more formal and emphatic.

Both forms can mean 'even if' or 'even though,' but differ in nuance. ても is more versatile and often appears in expressions like てもいい 'it's okay to (A)' for asking or giving permission. にしても carries a stronger hypothetical tone, like 'Even supposing that...' which ても alone doesn't necessarily convey. Both are used with question words, e.g. どこに行っても and どこに行くにしても 'no matter where you go', with the latter sounding more hypothetical.