§ 309. Out of the three classes into which the weak verbs in Anglo-Saxon are divided, only one takes a vowel before the d or t. The other two add the syllables -te or -de, to the last letter of the original word. The vowel that, in one out of the three Anglo-Saxon classes, precedes d is o. Thus we have _lufian_, _lufode_; _clypian_, _clypode_. In the other two classes the forms are respectively _bærnan_, _bærnde_; and _tellan_, _tealde_, no vowel being found. The _participle_, however, as stated above, ended, not in -de or -te, but in -d or -t; and in two out of the three classes it was preceded by a vowel; the vowel being e,--_gelufod_, _bærned_, _geteald_. Now in those conjugations where no vowel preceded the d of the præterite, and where the original word ended in -d or -t, a difficulty, which has already been indicated, arose. To add the sign of the præterite to a word like _eard-ian_ (_to dwell_) was an easy matter, inasmuch as _eardian_ was a word belonging to the first class, and in the first class the præterite was formed in -ode. Here the vowel o kept the two d's from coming in contact. With words, however, like _métan_ and _sendan_, this was not the case. Here no vowel intervened; so that the natural præterite forms were _met-te_, _send-de_, combinations wherein one of the letters ran every chance of being dropped in the pronunciation. Hence, with the exception of the verbs in the first class, words ending in -d or -t in the root admitted no additional d or t in the præterite. This difficulty, existing in the present English as it existed in the Anglo-Saxon, modifies the præterites of most words ending in -t or -d. § 310. In several words there is the actual addition of the syllable -ed; in other words d is separated from the last letter of the original word by the addition of a vowel; as _ended_, _instructed_, &c. § 311. In several words the final -d is changed into -t, as _bend_, _bent_; _rend_, _rent_; _send_, _sent_; _gild_, _gilt_; _build_, _built_; _spend_, _spent_, &c. § 312. In several words the vowel of the root is changed; as _feed_, _fed_; _bleed_, _bled_; _breed_, _bred_; _meet_, _met_; _speed_, _sped_; _rēad_, _rĕad_, &c. Words of this last-named class cause occasional difficulty to the grammarian. No addition is made to the root, and, in this circumstance, they agree with the strong verbs. Moreover, there is a change of the vowel. In this circumstance also they agree with the strong verbs. Hence with forms like _fed_ and _led_ we are in doubt as to the conjugation. This doubt we have three means of settling, as may be shown by the word _beat_. a. _By the form of the participle._--The -en in _beaten_ shows that the word _beat_ is strong. b. _By the nature of the vowel._--The weak form of _to beat_ would be _bet_, or _beăt_, after the analogy of _feed_ and _read_. By some persons the word is pronounced _bet_, and with those who do so the word is weak.