Melacha That Begins Before Shabbat

Background

1. The Mishna cites a dispute between Beit Hillel and Beit Shamai whether it is permitted to initiate a process that involves melacha if it starts before Shabbat and continue into Shabbat. For example, Beit Shamai forbids leaving dyes to soak in water, whereas Beit Hillel permit. The Gemara explains that Beit Shamai subscribes to Shevitat Kelim, meaning that there is a prohibition to have one's utensils do a melacha for oneself on Shabbat. Beit Hillel, however, don't accept this concept.
2. According to Beit Hillel, it is permitted to set up an animal trap before Shabbat even if the animal is trapped on Shabbat since the process was set up before Shabbat.
3. Similarly, it is permitted to leave a hose to water the grass if it was left on before Shabbat even if it continues to water the grass on Shabbat.

Practical Cases

1. According to Sephardic poskim, if one started a cycle in the washing machine before Shabbat, it is permitted to let in continue during Shabbat.

Sources

Category	Topic
Mitzvot of Shabbat	Kiddush Levana - Enjoying Shabbat - Fourth meal of Shabbat - Havdalah - Having a meal on Friday - In the Spirit of Shabbat - Kiddush - Lighting Shabbat Candles - Making Early Shabbat - Making one hundred Brachot on Shabbat - Preparing foods on Shabbat - Preparing for Shabbat - Shenayim Mikrah - Kavod Shabbat - Shabbos Davening - Seudat Shabbat - Seudat Shelishit - Lechem Mishneh - Motzei Shabbat - When Does Shabbat Start?
Restrictions of Shabbat	Allowing Carrying Using an Eruv Chatzerot - Animals on Shabbat - Asking a Jew to work on Shabbat - Asking a non-Jew to work on Shabbat (Amirah LeNochri) - Benefiting from a Violation of Shabbat (Maaseh Shabbat) - Books, notebooks, and papers - Brushing Teeth on Shabbat - Building a structure on Shabbat (Boneh) - Carrying on Shabbat - Cleaning the dishes - Cleaning and Folding Garments on Shabbat - Clearing the table - Cooking (Ofeh and Bishul) - Cosmetics on Shabbat - Dancing and clapping on Shabbat - Electricity on Shabbat - Eruv Chatzerot - Eruvin - Games on Shabbat - Getting dressed on Shabbat - Giving birth on Shabbat - Grinding (Tochen) - Handling objects on Shabbat (Muktzeh) - Infants on Shabbat - Introduction to the Modern Eruv - Kneading (Lash) - Mail on Shabbat - Medicine on Shabbat (Refuah on Shabbat) - Melacha That Begins Before Shabbat - Opening bottles and containers (Boneh) - Plants on Shabbat (Zoreah) - Preparing for after Shabbat (Hachana) - Reading on Shabbat (Daber Davar) - Recreation on Shabbat - Sechirut Reshut - Separating mixtures (Borer) - Squeezing fruits (Sechita) - Speaking on Shabbat (Daber Davar) - Taking a cruise over Shabbat - Taking measurements on Shabbat - Techum - Transactions on Shabbat - Transportation on Shabbat - Going to and Staying in the Hospital on Shabbat - Wages on Shabbat (Sachar Shabbat) - Washing one’s body on Shabbat
Melachos	Introduction to Melechet Machshevet - Marbeh Bshiurim - Plowing - Planting - Harvesting - Gathering - Threshing - Winnowing - Separating - Grinding - Sifting - Kneading - Baking and Cooking - Shearing - Laundering - Combing - Dyeing - Spinning - Mounting warp threads - Making two loops - Weaving - Unraveling fabric - Tying - Untying - Gluing, taping, or stapling - Ripping - Trapping - Slaughtering - Skinning - Tanning - Smoothing - Scoring - Cutting precisely - Writing - Erasing - Building - Demolishing - Completing a vessel - Extinguishing a flame - Kindling a fire - Carrying