Learn Japanese with Anime - If We See Each Other, We’ll Know (Your Name)

Analysis

確かなことが一つだけある

確か is a na-adjective meaning “certain”, modifying the noun こと meaning “thing”. When a na-adjective modifies the following noun, the hiragana な should be attached. That’s why it’s called a “na” adjective. So 確かなこと means “certain thing” or “something certain”.

Something (noun) が (particle) ある (verb) means “something exists” or “there is something”.

And you can add the quantities between が and ある. In this case, the quantity is 一つ. The numeral in kanji read as ひと represents “one” and it’s followed by the counter suffix つ which is used to count general things or abstract things.

And it’s followed by だけ (particle) meaning “only” so 確かなことが一つだけある means “there is only one certain thing”.

私たちは会えば絶対すぐにわかる.

私たち (pronoun) means “we”.

The は particle shows the preceding word 私たち is the topic in this sentence.

会えば means “if (we) meet”. It’s the conditional form of the verb 会う meaning “to meet”. To make a verb conditional form, take the plain form of the verb and switch the last hiragana which is from the う-line to the え-line （う→え）and attach ば. So the conditional form of 会う is 会えば.

絶対 (adverb) means “definitely”.

すぐに (adverb) means “immediately”.

わかる (verb) means “to know, find out or figure out” used when you finally understand something or someone.

There are two adverbs in a row followed by the verb, but each adverb affects different things. すぐに (immediately) simply modifies the following verb わかる which makes “(we’ll) know immediately”. And 絶対 (definitely) affects the whole すぐにわかる part so it’s like “it is definite that we’ll know immediately”.

So 私たちは会えば絶対すぐにわかる directly means “if we meet, it is definite that we’ll know immediately”.

Note

すぐに can be replaced with すぐ when used to mean “immediately” or “soon”.

着(つ)い(い)た(た)ら(ら)す(す)ぐ(ぐ)／す(す)ぐ(ぐ)に(に)電(でん)話(わ)して。
Call me as soon as you arrive.

すぐ can also express “short distance”. In this usage, it cannot be replaced with すぐに.

駅(えき)はす(す)ぐ(ぐ)（すぐに）そ(そ)こ(こ)です。

The station is right there.