亙(わた)る

to extend; to range over

亙(わた)って

across; throughout; over

長期(ちょうき)に亙(わた)る

to extend over a long period

多岐(たき)に亙(わた)る

to cover a wide range

広範囲(こうはんい)に亙(わた)る

to extend over a broad area

数日(すうじつ)に亙(わた)る

lasting several days

彼(かれ)の研究(けんきゅう)は多岐(たき)に亙(わた)る。

His research spans many fields.

その影響(えいきょう)は全国(ぜんこく)に亙(わた)る。

Its effects extend throughout the country.