The grammar you actually need for JFT-Basic

JFT-Basic does not have a grammar section. That is the first thing to understand about its grammar.

Grammar is tested indirectly — inside conversation questions, listening clips and reading texts — which means you are never asked to name a form. You are asked to understand what a sentence means, and a grammar point you can recite but not process at speed is worth nothing here.

The structures that decide answers

Roughly A2. In order of how often they determine a question:

Particles

は, が, を, に, で, と, から, まで, までに, も, の.

Particles carry the information that questions turn on — who did what to whom, when, by when, where. までに (by a deadline) versus まで (until) decides more listening and reading questions than any other single point on this list.

Verb forms

• Present and past, affirmative and negative. ます / ました / ません / ませんでした.
• て-form, and what attaches to it: 〜てください, 〜てもいいですか, 〜ています.
• ない-form, especially 〜ないでください and 〜なくてもいいです.
• Volitional-ish offers: 〜ましょうか.

Sentence-level

• から / ので — reason.
• が / でも — contrast. This one is a frequent trap: “normally 9:00, but 10:00 when it rains.”
• とき — when.
• まえに / あとで — before and after.
• 〜たほうがいいです — advice.

Adjectives

い- and な-adjectives, present and past, positive and negative, and comparison with より and いちばん.

The three that cost the most points

If you fix nothing else, fix these:

Structure	Why it decides questions
までに vs まで	Deadline versus duration. Arrive by 9:50 is not the same as stay until 9:50.
Negatives	とまりません, わすれないで, なくてもいい. One negative flips the entire answer.
が / でも contrast	The sentence gives two facts and the question asks about the second one.

Notice that all three are small. They are not advanced grammar; they are ordinary grammar that has to be processed instantly, under time pressure, sometimes in audio that plays once.

What you can leave alone

Keigo beyond the set phrases. Passive and causative. Conditional forms beyond the basics. Long subordinate clauses. These belong to JLPT N3 and above, and time spent on them is time not spent on the vocabulary that would actually move your score.

The exception is the handful of fixed polite expressions used whole at work — おさきに しつれいします, おつかれさまです, しつれいします. Those are phrases rather than grammar, and they do appear. See Conversation and Expression.

How to study it so it works under pressure

In sentences you could say aloud, not in a table. The exam requires processing, not recall, and a table is recall.

Through listening and reading, where grammar arrives at natural speed with everything else. Grammar drills teach you to recognise a form when you are looking for it. The exam never tells you to look for it.

With attention to what changed. When you get a practice question wrong, decide which of these it was: an unknown word, a misread grammar point, a timing failure, or carelessness. Only the second is a grammar problem, and people misattribute it constantly.

The free practice test explains every answer, which makes that attribution possible rather than guesswork.