when it comes to it

I get nervous.

私は緊張します

When it comes to it, I get nervous.

私はいざ緊張します

When it comes to the presentation, I get nervous.

私はいざ発表の時間になると緊張します

When it comes to the presentation, I get nervous in front of all those people.

私はいざ発表の時間になると大勢の人の前で緊張します

When it comes to the presentation, I get more nervous than I expected in front of all those people.

私はいざ発表の時間になると大勢の人の前で予想より緊張します