English Verb - To Lack Infinitive - to lack Present participle - lacking Past participle - lacked 1. Present Tense Singular I lack You lack He/she/it lacks Plural We lack You lack They lack 2. Present Progressive Tense Singular I am lacking You are lacking He/she/it is lacking Plural We are lacking You are lacking They are lacking 3. Past Tense Singular I lacked You lacked He/she/it lacked Plural We lacked You lacked They lacked 4. Present Perfect Tense Singular I have lacked You have lacked He/she/it has lacked Plural We have lacked You have lacked They have lacked 5. Present Perfect Progressive Tense Singular I have been lacking You have been lacking He/she/it has been lacking Plural We have been lacking You have been lacking They have been lacking 6. Past Progressive Tense Singular I was lacking You were lacking He/she/it was lacking Plural We were lacking You were lacking They were lacking 7. Past Perfect Tense Singular I had lacked You had lacked He/she/it had lacked Plural We had lacked You had lacked They had lacked 8. Past Perfect Progressive Tense Singular I had been lacking You had been lacking He/she/it had been lacking Plural We had been lacking You had been lacking They had been lacking 9. Future Tense Singular I will lack You will lack He/she/it will lack Plural We will lack You will lack They will lack 10. Future Progressive Tense Singular I will be lacking You will be lacking He/she/it will be lacking Plural We will be lacking You will be lacking They will be lacking 11. Future Perfect Tense Singular I will have lacked You will have lacked He/she/it will have lacked Plural We will have lacked You will have lacked They will have lacked 12. Future Perfect Progressive Tense Singular I will have been lacking You will have been lacking He/she/it will have been lacking Plural We will have been lacking You will have been lacking They will have been lacking