Postscript: Romaji, color-coding & translation by mink.

Underlined name has the higher/main melody.

For this song, both girls sing the chorus in unison, but there's also a separate cut of one of the girls doing the higher harmonization, which I'm guessing is Kago...

好きよ好きよ　キャプテン
テニス焼けの　笑顔
遠い町へ行ってもう帰らないの

教室から見つめたの　テニス・ボール打つ姿
汗にまみれた胸が　とても眩しかったのね
今日もひとりたたずめば肩をボンと叩かれて
涙拭けって優しい声　今も聞こえそう

好きよ好きよ　キャプテン
長い髪が似合う
私あこがれてた　ひとつ上級生

練習あと校庭で待ちあわせた　イチョウの木
ラケット胸に彼と二人　夕陽を見たわ
また逢う日もあるだろと　白い歯みせ笑ってた
兄貴のようにおでこにキス　さよならをしたの

好きよ好きよ　キャプテン
忘れないわきっと
生きることと恋を教えてくれたの

好きよ好きよ　キャプテン
忘れないわきっと
生きることと恋を教えてくれたの

Suki yo suki yo KYAPUTEN
TENISUyake no egao
Tooi machi e itte mou kaeranai no

Kyoushitsu kara mitsumeta no TENISU BOORU utsu sugata
Ase ni mamireta mune ga totemo mabushikatta no ne
Kyou mo hitori tatazumeba kata wo BON to tatakarete
namida fukette yasashii koe ima mo kikoesou

[Ts/Ka] Suki yo suki yo KYAPUTEN
[Ts/Ka] Nagai kami ga niau
[Ts/Ka] Watashi akogareteta [All] hitotsu joukyuusei

Renshuu ato koutei de machiawaseta ICHOU no ki
RAKETTO mune ni kare to futari yuuhi wo mita wa
Mata au hi mo aru daro to shiroi ha mise waratteta
Aniki no you ni odeko ni KISU sayonara wo shita no

[Ts/Ka] Suki yo suki yo KYAPUTEN
[Ts/Ka] Wasurenai wa kitto
[Ts/Ka] Ikiru koto to koi wo [All] oshiete kureta no

[Ts/Ka] Suki yo suki yo KYAPUTEN
[Ts/Ka] Wasurenai wa kitto
[Ts/Ka] Ikiru koto to koi wo [All] oshiete kureta no

I love you, I love you, captain
Your tennis court-burned smile
You went to a faraway city and won't return

I watched you from the classroom as you struck the tennis ball
Your chest was so bright, covered with sweat
Even today, lingering here alone, it's like I can still hear your gentle voice
Tapping me on the shoulder and telling me to wipe away my tears

I love you, I love you, captain
Long hair suits you best
The one upperclassmen I admired

On campus after your practice
We met at the ginko tree
As you held the racket to your chest
We watched the sun go down together

Surely we'll meet again someday
You smiled, showing your white teeth
Kissing me on the forehead like an older brother
You said goodbye

I love you, I love you, captain
I will never forget you
You taught me how to live and love

I love you, I love you, captain
I will never forget you
You taught me how to live and love