He was unable to recall the exact amount of time he had spent on his research, but it was extensive.
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Hiː wəz ʌnˈeɪ.bəl tu ˈriː.kɑːl ðə ɪɡˈzækt əˈmaʊnt əv taɪm hiː hæd spɛnt ɒn ˈhɪz rɪˈsɜːrtʃ bʌt ɪt wəz ɪkˈstɛnsɪv. Hi ues aneibel tu rikal de iɡsèkt emaunt ev taim hi hèd spènt on his riserrci bat it ues ikstènsiv.
Non riusciva a ricordare l'esatta quantità di tempo trascorsa nella sua ricerca, ma era significativa.
Hiː wəz ʌnˈeɪ.bəl tu ˈriː.kɑːl ðə ɪɡˈzækt əˈmaʊnt əv taɪm hiː hæd spɛnt ɒn ˈhɪz rɪˈsɜːrtʃ bʌt ɪt wəz ɪkˈstɛnsɪv. Hi ues aneibel tu rikal de iɡsèkt emaunt ev taim hi hèd spènt on his riserrci bat it ues ikstènsiv.