もえ漫画 005: キャプテン永時
これを [korewo] - means “this".
決めれば [きめれば (kimereba)] - Means “if I score". The plain verb is “決める” [きめる (kimeru)] which means "to decide” or “to score” when used in a conversation regarding sports. The “-れば” at the end is a conditional which expresses an “if” condition.
きっと [kitto] - means “certainly”, “surely” or “undoubtedly”.
僕 [ぼく (boku)] - means “me/I”. One of the informal Japanese personal pronouns used by male. Some female characters however will use “僕” instead of “あたし” [atashi] which is an informal pronoun used by female - these type of girls are called “ボクっ娘” [ぼくっこ (bokukko)] and are considered to be moe to some.
好きになる [すきになる (sukininaru)] - means "to come to like” or “to fall in love”. This word is comprised of the word “好き” which means “like/love” and “-になる” which means “to become”.
がんばれ [ganbare] - means "go for it!" or "you can do it!". The original verb is がんばる [ganbaru].
いっけえええぇ [ikkeeee] - the original word is "行け" [いけ (ike)] and its plain verb is "行く" [いく (iku)] which means "to go". It can also be interpreted as "you're mine!" or "take this!" when written in an exaggerated form like above.
決まった [きまった (kimatta)] - means "to have scored". Past tense for "決める".
そんな [sonna] - "そんな" is usually used as an pre-nominal adjective but when used alone like above, it can be interpreted as "Noooooo", "why is this happening to me?" or something similar.
ドン / ガン / バン / ボコッ
ドン [どん (don)] / ガン [がん (gan)] / バン [ばん (ban)] / ボコッ [ぼこっ (bokko)] - these types of onomatopoeias are used to express a sound of something being hit.