I think the words 'あげた', 'かりた', and 'よんだ' are not in the dictionary form. Those are conjugated forms of the verbs whose dictionary forms (i.e., [終止形]{しゅうしけい}, ending form) are 'あげる', 'かりる', and 'よむ', attached with the conjugated auxiliary verbs whose 終止形 are 'た' and 'だ'.
It would be useful to remember that, in modern Japanese, the 終止形 of all verbs ends with the '-u' sound. For example, ager'u', karir'u', and yom'u', in the above verbs.
'あげた' is a combination of the verb 'あげる' and the auxiliary verb 'た', which makes the tense of the preceding verb to the past. The verb 'あげる' in the phrase 'あげた' is conjugated to [連用形]{れんようけい} (form to precede a verb, adverb, or auxiliary verb) 'あげ' in order to attach to the auxiliary verb 'た'. Then, 'た' in 'あげたほん' is conjugated to the [連体形]{れんたいけい} (form to precede a noun) 'た', which happens to have the same pronunciation as the 終止形, in order to attach to the noun 'ほん'.
Similar structure is also in 'かりた'.
'よんだ' is a combination of the verb 'よむ' and the auxiliary verb 'だ', which also indicates the past tense. 'よむ' is conjugated to 連用形 'よみ' to connect to 'だ'. Then, 'だ' is at the end of the sentence. So, it is in the 終止形 'だ'. In the resulting phrase 'よみだ', the middle 'み' is modified to 'ん' for the sake of easy pronunciation. (This is called [撥音便]{はつおんびん}.) This is how you get 'よんだ'.
That's a brief explanation. For more, learn Japanese conjugation ([活用]{かつよう}) system for verbs (as well as auxiliary verbs, adverbs, adjectives, and others!) as macraf wrote. Have fun!
