OET interlinear HERO (JDG) 20:3

uW Translation Notes:

Note 1 topic: figures-of-speech / explicit

וַֽ⁠יִּשְׁמְעוּ֙ בְּנֵ֣י בִנְיָמִ֔ן כִּֽי־עָל֥וּ בְנֵֽי־יִשְׂרָאֵ֖ל הַ⁠מִּצְפָּ֑ה

(Some words not found in UHB: and=they_heard sons_of Binyāmīn that/for/because/then/when gone_up sons_of Yisrael (the),Mizpah and=they_said sons_of Yisrael tell how it_happened the,evil (the),this )

The author assumes that readers will recognize that he means the Benjaminites heard about this assembly but did not join it. This indicates that they were going to defend the men of Gibeah rather than join in punishing them. You could indicate this explicitly in your translation if that would be helpful to your readers. Alternate translation: [Now the sons of Benjamin heard that the sons of Israel had gone up to Mizpah, but they did not join the assembly, because they were going to defend rather than punish men from their own tribe]

Note 2 topic: figures-of-speech / explicit

וַ⁠יֹּֽאמְרוּ֙ בְּנֵ֣י יִשְׂרָאֵ֔ל

(Some words not found in UHB: and=they_heard sons_of Binyāmīn that/for/because/then/when gone_up sons_of Yisrael (the),Mizpah and=they_said sons_of Yisrael tell how it_happened the,evil (the),this )

The author assumes that readers will know that the Israelites were speaking to the Levite. You could indicate this explicitly in your translation if that would be helpful to your readers. Alternate translation: [And the sons of Israel said to the Levite]